Various forms of identification cards or credit cards have come into exceedingly widespread use to designate the owner as a person to whom credit may be extended. These cards have been successful largely because they enable the owner to avoid carrying significant amounts of cash. However, the use of the cards and similar devices has not been without certain attendant difficulties. For example, the owner of a credit card may become irresponsible due to financial reverses, whereupon he may incur a large indebtedness based on his credit card, which indebtedness may not be recoverable.
Another problem in the use of cards, plates, and other devices employed to identify a person for credit, stems from the loss of such devices. That is, the owner of a credit card may lose his card or it may be stolen, whereupon an unauthorized bearer may make large purchases supported by the credit card. Generally, in such a situation, either the owner of the credit card or the issuing organization incurs a substantial loss.
In view of these difficulties, some attempts have been made to control the use of credit cards. For example, it has been proposed to utilize a central computer which maintains a current balance for each issued credit card. A warning is then provided in the event a credit card is used to excess. However, in general, systems of this type have been limited for two reasons. First, the requisite computer is inherently expensive, both in acquisition and in maintenance. However, systems implementing automatic funds transfer may justify the cost. Second, it is a requirement of the system that upon each presentation of the credit card, communication must be established with the computer, e.g. terminals must be "on-line". As a result, the usability of the card may be quite restricted or the necessary communication system reaches vast proportions.
Therefore, considerable need exists for a practical system, for use in cooperation with credit cards and related devices, which system may be effectively operated with terminals either "on-line" or "off-line" to control the use of these devices and thereby minimize financial loss, both to the persons to whom the cards are assigned (owners) and to the issuing organization. In this regard, the present invention is based upon the recognition of the expense and difficulty of perpetually operating a remote terminal system in an "on-line" configuration. Specifically, the present invention accommodates "off-line" operation of remote terminals, for example, in the event of a communication line failure, a central equipment failure or shut down, or by design.
As disclosed in U.S. Pat. No. 3,891,830, the significance of time or discrete time intervals as a factor in controlling the use of a credit card has been recognized. The present invention contemplates control of identification devices based on use of such devices as related to a particular interval of time as in an integral component of a system which includes a plurality of terminals, at least part of which are coupled for communication with a central unit.
In a system utilizing a central computer to maintain a current balance (or related data) for each credit card in use, communication between a remote station and the central unit is a requisite to each operation of any remote station. Otherwise, the current-balance data could not be consulted prior to consummating a proposed transaction. Of course, the system might employ alternative control criteria during limited lapses of communication; however, as a consequence, the current-balance data in the central unit may become incorrect, which would bear heavily on subsequent control as well as funds-transfer considerations. Also, the alternative control criteria may be difficult to preserve in alternate "off-line" and "on-line" uses of the card.
The system of the present invention may be embodied as a central unit and a plurality of remote stations that are operated in either an "off-line" or an "on-line" configuration in cooperation with an identification card or the like, which bears a recording medium thereon. The system incorporates means to indicate a predetermined interval of time, and further includes means for sensing the recording medium on the card to provide an indication of the last time when the card was used. Furthermore, the system as disclosed records data on the extent of use of the card during the interval of last use and the extent of such use at terminals in an "off-line" configuration.